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\begin{document}
\begin{tabular}{lccc}
\multicolumn{4}{c}{Impact of treatment on overall grade} \\ \hline
 & (1) & (2) & (3) \\
VARIABLES & y1 & y1 & y1 \\ \hline
 &  &  &  \\
1bn.\_predict & -0.001 & -0.000 & -0.009** \\
 & (0.001) & (0.000) & (0.004) \\
2.\_predict & -0.002 & -0.002 & -0.012** \\
 & (0.002) & (0.001) & (0.005) \\
3.\_predict & -0.004 & -0.004 & -0.016** \\
 & (0.003) & (0.003) & (0.007) \\
4.\_predict & -0.007* & -0.006 & -0.024** \\
 & (0.004) & (0.004) & (0.009) \\
5.\_predict & -0.005* & -0.006 & -0.011** \\
 & (0.003) & (0.004) & (0.004) \\
6.\_predict & -0.008* & -0.006 & -0.003* \\
 & (0.005) & (0.004) & (0.002) \\
7.\_predict & -0.005* & -0.005 & 0.006** \\
 & (0.003) & (0.003) & (0.003) \\
8.\_predict & -0.002 & -0.002 & 0.012** \\
 & (0.001) & (0.001) & (0.005) \\
9.\_predict & 0.000 & 0.001 & 0.015** \\
 & (0.000) & (0.000) & (0.006) \\
10.\_predict & 0.003* & 0.003 & 0.014** \\
 & (0.002) & (0.002) & (0.006) \\
11.\_predict & 0.004* & 0.004 & 0.010** \\
 & (0.002) & (0.003) & (0.004) \\
12.\_predict & 0.005* & 0.005 & 0.007** \\
 & (0.003) & (0.003) & (0.003) \\
13.\_predict & 0.005* & 0.004 & 0.007** \\
 & (0.003) & (0.003) & (0.003) \\
14.\_predict & 0.004* & 0.004 & 0.003* \\
 & (0.002) & (0.002) & (0.001) \\
15.\_predict & 0.003* & 0.003 &  \\
 & (0.002) & (0.002) &  \\
16.\_predict & 0.003 & 0.002 &  \\
 & (0.002) & (0.002) &  \\
17.\_predict & 0.002 & 0.002 &  \\
 & (0.001) & (0.002) &  \\
18.\_predict & 0.002 & 0.002 &  \\
 & (0.001) & (0.002) &  \\
19.\_predict & 0.002 & 0.001 &  \\
 & (0.002) & (0.001) &  \\
20.\_predict & 0.001 &  &  \\
 & (0.001) &  &  \\
 &  &  &  \\
 Observations & 708 & 708 & 707 \\ \hline
\multicolumn{4}{c}{ Standard errors in parentheses} \\
\multicolumn{4}{c}{ *** p$<$0.01, ** p$<$0.05, * p$<$0.1} \\
\end{tabular}
\end{document}
